Editing Generation ship (section)

===Size===
For a spacecraft to maintain a stable environment for multiple generations, it would have to be large enough to support a community of humans and a fully recycling ecosystem.<ref >{{cite arXiv | last1=Marin | first1=F. | last2=Beluffi | first2=C. | title=Computing the minimal crew for a multi-generational space travel towards Proxima Centauri b | date=2018 | class=astro-ph.IM |eprint=1806.03856}}</ref> A spacecraft of such a size would require much energy to accelerate and decelerate. A smaller spacecraft, while able to accelerate more easily and thus make higher cruise velocities more practical, would reduce exposure to cosmic radiation and the time for malfunctions to develop in the craft, but would have challenges with resource metabolic flow and ecologic balance.<ref>{{cite web |author1=Kim Stanley Robinson |title=What Will It Take for Humans to Colonize the Milky Way? |url=https://www.scientificamerican.com/article/what-will-it-take-for-humans-to-colonize-the-milky-way1/ |work=[[Scientific American]] |access-date=January 31, 2019 |language=en |date=January 13, 2016}}</ref>